Pressure-gage.



No. 845,065. PATENTED FEB. 26, 1907. M. DUNN.

EEESSU'EE GAGE. APPLIOATION YILBD MB..15,1906.

2 SHEETS-SHEET l.

- I l i MMU .Sie ATTQENEYS No. 845,065. ATBNTBD FEB. 26, 1907.

M. DUNN.

PRESSURE GAGE.

APPLICATION FILED MAB.. l5, lQG.

Z SHEETS-SHEET 2.

i F 4. W|TNESSES /by NVENTR ATTORNEYS,

MICHAEL DUNN, OF COLUMBUS, OHIO PRESSURE-GAGE.

Specicatior of Letters Patent.

Patented Feb. 26, 1907.

Application filed March 15.1906. Serial N0, 306,152-

To all whom, I? may concern:

Beit known that I, MICHAEL DUNN, a citizen of the United States,residing` at Columbus, in the county of Franklin and State of Ohio, haveinvented certain new and useful Improvements in Pressure-Gages, of whichthe following` is a specification.

My invention relates to new and useful improvements in pressure-gages.

The object of the invention is to provide a simple gage of superiorconstruction adapted to be employed to register the pressure used inpressing Wheels on axles, piston-heads on piston-rods, crank-pins inlocomotive-wheels and the like, 6to.

Another feature is the arrangement whereby a diagram-card or paperribbon is employed and the number of inches indicated by lines runningin one direction and the pressure indicated by lines running in anopposite direction.

Finally, the object of the invention is to provide a device of thecharacter described that will be strong, durable, and e'ih cient and onein which the several parts will not be liable to get out of workingorder.

With the above and other objects in view the invention consists of thenovel details of construction and operation, a preferable embodiment ofwhich is described in the speciiication and illustrated in theaccompanying drawings, wherein- Figure 1 is a plan view with the coverremoved. Fig. 2 is a longitudinal vertical sectional view. Fig. 3 is atransverse vertical sectional view of the casing, showing thepiston-cylinder and the slide in elevation, the paper ribbon or tapebeing broken away to show parts lying in the rear thereof and Fig. 4 isan elevation of a portion of the paper ribbon or tape.

In the drawings, the numeral 1 designates a housing or casingrectangular in shape and provided with a hinged cover or top 2. Thiscasing is designed so as to conceal the parts arranged therein, and thecover 2 may be fastened or locked by any suitable means. Near the centerof the casing and the top and bottom thereof longitudinal guide-rods 3are arranged. On these rods a carriage 4, adapted to travellongitudinally of the casing, is arranged. The carriage 4 comprises aVvertical plate 6, which slides in guides 5, secured to the ends of thecasing at the top and bottom thereof, so as to permit the cover 2 to beraised without disturbing the same. From the rear side of the plate 6 ashelf or platform 7 extends horizontally a short distance above thebottom of the casing and the lower rod 3. From this shelf a lug S,engaging freely about the lower rod 3, depends, while a hanger 9,secured to the rear side of the plate 6, eX tends upwardly and engagesfreely about the upper rod 3. The rods 3 receive coiled springs 10,which bear against the lug 8 and hanger 9 when extended and act to holdthe carriage at the right-hand end of the casing, as shown in Figs. 1and 2. rIhe carriage is adapted to be moved against the tension of thesesprings, which are compressed, so that when the carriage is released thesprings act to return the same to its normal position. At one end theplate 6 is rounded, as indicated at 1l, and is provided near itsopposite end with a vertical slot 12, having one side rounded.

About the end 1.1 and through the slot 1.2 a paper ribbon ordiagram-tape 14 is passed, so as to extend across the face of the plate6 in a vertical plane. On the shelf 7 pins l5 are arranged and receivespools or arbors 16, about which the tape is wound. This tape issuitably lined, and as an instance of such lining I have shown in Fig. 4a portion of the tape on which vertical lines 17 are provided toindicate inches and horizontal or longitudinal lines 18 for indicatingthe pressure. lIhe manner of carrying out this operation will behereinafter described.

For traversing the carriage 4 I arrange on the front side of the plate 6a pair of pulleys or sheaves 19, while at the left-hand end of thecasing a suitable pulley or sheave 20 is disposed. A cord 2l, secured tothe left-hand end of the casing, is passed over the upper pulley 19,then back about the pulley 20, from there over and about the lowerpulley 1Q, and back through the end of the casing, the cord being ofsuitable length and having its free end attached to the ram or othermovable part, so that the carriage will be moved to the left as the rammoves out and allowed to be returned by the springs 10 when the rain ismoved in.

The casing 1 is mounted on the upper end of a cylinder or piston casing22, which latter is provided with a lower contracted portion 23. Apiston-rod 28, passing through the parts 22 and 23, also extends throughthe bottom of the casing and carries on its upper end a barrel 24, inwhich is arranged an indelible pencil 25, the latter having a washer ICO26 'fixed thereto, against which a coiled spring 27, confn'ied withinthe barrel, bears. rlhis barrel and the pencil are placed atsubstantially right angles to the diagram-tape, so that the spring 27acts to hold the pencil in contact therewith. About the piston-rod 2S Isecure a piston-head 29, against which a coiled resistance-spring BObears, the latter being confined within the cylinder 22. A suitablepacking 3l 'is provided about the lower end of the piston-rod, as shownin 2, while a thinible 32, screwed into the lower end of the reducedportion 23, has connection with the pressure ineans, so that the sainepressure exerted on the work is exerted on the lower end of the piston28. in this way the spring 3() resists the pressure and allows thepiston-rod to ascend in proportion to the increase of the pressure.

The operation is as follows: The cord 21 being connected to the rain orother inovable part causes the carriage, and thus the diagram-tape 14C,to travel to the left in relation to Figs. i and 2. At the saine timethe pressure exerted on the piston-rod 2S causes the saine to ascend, sothat the pencil 25 traces the inovenient on the diagram-sheet. in thisway both the travel of the rain and the pressure are recorded. After therain is drawn in and the pressure relieved the springs 10 return thecarriage and the spring 3() forces down the piston and the pencil, thusreturning` the latter to its starting-point. n Fig. i the heavy blacliline illustrates the travel of the pencil or the niarliing of the pencilon the diagram-sheet as the saure travels, indicating that the worl; hasbeen properly carried out. After each successive operation the tape iswound by any suitable ineans, so that a fresh diagramL is presented forthe next operation. it is obvious that should the pressure vary thelongitudinal part of the line 33 would Waver, as the pencil would becaused to either ascend or descend, and likewise should the inovernentof the ram vary the curved part of the line 33 would be irregular. Bythis ineans one is enabled to ascertain the exact travel of the rain andthe pressure used on each piece of work.

Vhat l claini isi. In a device of the character described, theconibinatioi'i with an indicator casing, of a piston-casing supportedupon the upper end of said indicator-casing, a plunger arranged in thepiston-casing and projecting into said indicator-casing, guide-rodsextending longitudinally of the indicator-casing, a carriage removablelongitudinally in said indicatorecasing and having portions whichencircle said guide-rods, springs bearing between said encirclingportions and the indicator-casing, said springs tending to force saidcarriage toward one end of the casing, a n arking-point carried by theplunger and adapted to inove adjacent said carriage, said carriageconlprising a vertical front portion and a horizontal portion, andtape-supporting rolls mounted upon said horizontal portion. l

'In a device of the character described, the combination with a casing,of guide-rods nrounted in said casing, a carriage mounted to travel insaid casing and having portions which. encircle said guide-rods, springsencircling the guide-rods and bearing between. said portions and one endof the casing, tapesupporting rolls nrounted to travel with thecarriage, nzeans for in oving said carriage against the tension of thesprings, a pressureo )era-ted piston, and a marking-point carried bysaid piston which travels adj acont the face of the carriage.

in testimony whereof i atl/ix niy signature inV presence of twowitnesses.

MICHAEL DUNN.

YWitnesses 1 MARY DUNN, MARY KENNEY.

